Could we ever reach a parallel universe? Here's what physicists really think

The idea that parallel universes exist is something we have often seen in movies and TV shows, but how true is it actually? Physicists and scientists around the world have been exploring the possibility of parallel universes for decades. But as of now, we have not found any direct evidence that proves it exists. But that's not all.

Here’s a look at some of the leading theories and what scientists say about how true the possibility of parallel universes really is.

One of the leading theories says that if space goes on forever, then the arrangement of matter within it would eventually have to repeat. This is because there are only a limited number of ways particles can be arranged. To explain this, physicist Brian Greene gave an example of shuffling cards. 

He said, "Now, if you shuffle that deck, there's just so many orderings that can happen. If you shuffle that deck enough times, the orders will have to repeat. Similarly, with an infinite universe and only a finite number of complexions of matter, the way in which matter arranges itself has to repeat."

Our universe may not have been the only universe created from the Big Bang. Instead, there are other big bangs which may have created many separate bubbles of space and time, each one sealed off from the rest. 

According to Brian Greene, if this version of the multiverse is correct, that would mean that getting from our universe to another one would be just as impossible as traveling back before our own Big Bang happened. In other words, these universes are cut off from each other entirely.

Quantum physics says that every choice we make in daily life creates a new branch of reality. And this means that countless versions of us could already be living simultaneously across different universes.

Explaining this, Dr. Michio Kaku, theoretical physicist, futurist, and bestselling author of “Quantum Supremacy: How the Quantum Computer Revolution Will Change Everything,” shared that our universe is heading towards a "big freeze," which is an extremely cold, slow ending, and that future technology might eventually make it possible to travel between universes.

What if another universe were just beyond dimensions we cannot perceive yet? This is the idea brought up by astrophysicist Neil deGrasse Tyson. He has shared that if higher-dimensional universes exist, then moving between them might not be as far-fetched as it sounds.

In an interview, he explained, “We have some cogent theoretical expectations that our universe might be just one of many spawned from this.” He added, “We thought the Sun was special; it’s one of a hundred billion suns. The galaxy’s special? No, there are a hundred billion galaxies. We have one universe, or do we? The track record says why should there only be one? Be open to the possibility that you don’t live in the majority universe that’s out there.”